A vacuum heat insulator comprises a sleeve which defines a vacuum chamber inside and at least one layer (GB layer) which comprises a thermoplastic resin and satisfies the following formula: thickness times thermal conductivity times oxygen porosity is less than 10<-6>, in metric units. At least one GB layer comprises a thermoplastic resin and an inorganic layer combination. The insulator also comprises a core material inside the sleeve, plus a structured hollow body with the core material inside it. One GB layer satisfies the formula: volume divided by (oxygen porosity times inner surface area) is in the range from 100-5000, all in metric units and the porosity being at a humidity of 50%.
